Ringforts, known in Irish as raths, were the enclosed farmsteads of early medieval Ireland, typically encircled by one or more earthen banks and ditches to demarcate a family's living space and livestock enclosure. This one at Cormackstown survives as a roughly oval enclosure, measuring 44 metres north to south and 32.5 metres east to west, its gravelly earth and stone bank still standing up to 1.6 metres on the exterior face. There is no trace of a fosse, the defensive ditch that often accompanies such sites, and no identifiable entrance feature remains.

What makes the site particularly telling is the record of its own undoing. Ordnance Survey maps from 1843 and again from the 1952 to 1953 survey both show a lime kiln positioned in the eastern sector of the fort. A lime kiln is a stone-built furnace used to burn limestone into quicklime, widely used in agriculture to reduce soil acidity and in construction as a mortar ingredient. The kiln's presence explains the substantial damage to the eastern bank, where a large portion has been quarried out, presumably to supply the raw limestone the kiln required. The north-eastern stretch of the bank has been truncated as a result. It is a familiar kind of archaeological irony: the same durable stone construction that helped an ancient enclosure survive for over a thousand years eventually made it a convenient quarry for a later generation's entirely practical purposes.